Mr Cameron had earlier admitted that the Conservatives may not have "sealed the deal" with voters.

"You never seal the deal until you really win people's trust... a battle we have to fight every day, every week, every month," he told Andrew Marr.

But he dismissed recent poll findings that indicated a reduced Conservative lead since Mr Brown's Labour party conference speech and said the unity of the Tory party made it more suited to government than Labour's fractured state.

Mr Cameron also rejected Labour claims that the Conservatives believe British society to be "broken", saying: "I'm not a pessimist - I think it can be mended."

He called himself a "fiscal conservative" and spoke of plans to increase the Bank of England's power to rescue ailing banks, as well as outlining Conservative plans to permit thousands of non-selective schools to be introduced into the state sector.

And when questioned whether he would be interested in taking part in a televised debate with the prime minister, similar to that held between US presidential hopefuls Barack Obama and John McCain this week, Mr Cameron's reply was an emphatic: "Yes, yes, yes."